A study presented on Monday by the Alzheimer's Association International Conference in Paris revealed that ex-NFL players are more susceptible to developing mild cognitive impairment (MCI) than non-football-playing men of the same age.

MCI is, as Time's Alice Park notes, a form of dementia that leads to Alzheimer's and, unsurprisingly, the development of MCI relates directly to the number of violent hits and jarring shots to the head that football players take during the course of their career.

"The players who were impaired looked exactly like the typical clinical MCI patient in terms of their profile," Christopher Randolph, a professor of neurology at Loyola University Medical Center who led the study, said. "That supports our hypothesis that what we are dealing with is an earlier expression of MCI or AD in these players than would be expected otherwise."

The most terrifying aspect of the study (in which researchers at the University of North Carolina at Chapel Hill also assisted)? Helmets won't prevent this brain damage.

"The harder the stop, the more movement you have in the brain tissue; you stretch nerve fibers, tear fibers and bruise things," says Randolph. "So helmets are not going to protect you."

Randolph believes that changing practice habits could reduce the damage done to players' heads but that it could be difficult to reduce the amount of stress in games.

Regardless of the scientific evidence relating to reducing stress in games, though, it's obvious that decreasing the number of helmet-to-helmet hits that occur will significantly impact players' brains in a positive manner.